ISCSI Initiator configuration on HPUX

Any initiator configuration has following steps to be performed in order, for the initiator, to login onto the target so that one could present storage over ISCSI.

1-    Install the initiator
2-    Configure it to login onto the target



================    1    ==================

As first case, i'll install initiator on HPUX server (in my case its HPUX v2).

i.     Download the initiator software from HP's site.
       http://www.hp.com/products1/serverconnectivity/storagesnf2/iSCSI_sw_ini.html

       One should have login on HP's site. Initiator software is free to download and no license is
        required.
ii.    Downloaded file will be with .depot extension. Run software installation like follow:
       #swinstall -s /path_to_depot/*ISCSI*.depot
       Compelet the installation.
       You will find software binaries in /opt/iscsi and startup in /sbin/init.d/iscsi


================    2    ==================

Configuration consists of following steps.

i.    Change / Display the iscsi initiator name if you want to, using following commands:
      #/opt/iscsi/bin/iscsiutil -l  ---- Command will show current iscsi initiator name and other settings.
      #/opt/iscsi/bin/iscsiutil -i -N new_name_in_inq_format
ii.   Now add your iscsi target using the following command
      #/opt/iscsi/bin/iscsiutil -a -I IP_of_iscsi_target
iii.  Then run /sbin/init.d/iscsi start  --- and check iscsi target server if your initiator name is listed
       there. Now  you can present the disk/disks and can verify with #ioscan -fnC disk; insf -eC disk; 
       ioscan -funC disk. Your new disks should be visible on initiator name by now. Good Luck!

Linux 6 HA setup with Oracle

Note: 1) Blog is intended for people with good knowledge of Linux as OS and shell as a tool.
          2) Steps are extracted from RHEL 6.x HA implementation
Like every HA/clustering technology, making any service (DB,NFS,web server or any custom script) is accomplished by going through
1-     Configuring two servers in cluster / Preparing the machine/servers to look for each other
2-     Configuring the required service to fail over in event of some hardware/network failure.

####################      1      #####################
For Linux, list of per-requisites is given as:
i.          Backup existing /etc/yum.repos.d/rhel-source.repo file, and edit this file as shown below.
[rhel-local-base] 
gpgcheck=1 
name=Red Hat Enterprise Linux $releasever - $basearch - DVD
baseurl=file:///mnt 
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release

[rhel-local-HA] 
gpgcheck=1 
name=Red Hat Enterprise Linux $releasever - $basearch - DVD
baseurl=file:///mnt/HighAvailability 
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release

[rhel-local] 
gpgcheck=1 
name=Red Hat Enterprise Linux $releasever - $basearch - DVD
baseurl=file:///mnt/LoadBalancer 
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release

[rhel-local-RS] 
gpgcheck=1 
name=Red Hat Enterprise Linux $releasever - $basearch - DVD
baseurl=file:///mnt/ResilientStorage 
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release

[rhel-local-SF] 
gpgcheck=1 
name=Red Hat Enterprise Linux $releasever - $basearch - DVD
baseurl=file:///mnt/ScalableFileSystem 
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release

[rhel-local-Server] 
gpgcheck=1 
name=Red Hat Enterprise Linux $releasever - $basearch - DVD
baseurl=file:///mnt/Server 
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release  

and run
       

rpm –import <location_on_DVD>/RPM-GPG-KEY-redhat-release 

  
I assumed that you have DVD (Linux 6x in my case) in DVD drive.

  ii-       Install following software
    a.    cman
    b.    rmanager
    c.    luci
    d.    ricci
    e.    GFS
    f.    clvmd


OR

Alternatively you can use

#yum groupinstall "HighAvailability"
#yum groupinstall "LoadBalancer"
#yum groupinstall "ResilientStorage"
#yum groupinstall "ScalableFileSystem"

Remember to restart yum after adding above repos.

iii-    you must have 5 IPs and 4 NIC interfaces available for the systems.

iv-    Next is to configure services
       a) disable and turn off iptables with #chkconfig iptables off and #service iptables stop
       b) disable and turn off selinux with #chkconfig selinux off and #service selinux stop
       c) enable and run luci with #chkconfig luci on and #service luci start
       d) enable and run ricci with #chkconfig ricci on and #service ricci start
       e) enable and run rmanager with #chkconfig rmanager on and #service rmanager start
       f) enable and run clvmd with #chkconfig clvmd on and #service clvmd start

Note: After luci is started, it should be accessible with https://hostname_or_IP:8084. Sample is given as:


v-    Reset luci's password - in case!

vi-    Next step is create fence - in my case i have used HP's iLO as a fence. following url can help you configure the fence.
http://h10025.www1.hp.com/ewfrf/wc/document?cc=us&lc=en&dlc=en&docname=c03138211

Use luci's GUI to create fence rather editing cluster configuration as presented in HP's link.

vii-    System's /etc/hosts should look like below and NICs on both hosts should be configured accordingly.
                   

192.168.0.1   labnode1

192.168.0.2   labnode2

192.168.0.3   service_VIP

192.168.0.4   labnode1_hb

192.168.0.5   labnode2_hb

viii-    Run and configure cman for start as
            #chkconfig cman on; service cman start

after this onward, both systems are ready to be configured/bundled in a cluster - you name it.

ix-    login luci and add nodes and then create cluster
on shell #clustat command can acknowledge the cluster status. systems are ready to be configured to run your service (in this case Oracle) in HA configuration.

Note: when adding nodes in luci, use labnode1_hb and labnode2_hb as your cluster node names.  
        You put heartbeat link node name. This is how REHL HA uses heartbeat link to check each 
        other’s health, therefore determine whether fencing each other in case of the other node 
        fails to responds



################    2     #################

For any service to be configured in cluster with HA/LB functionality, one should understand / have the followings:

    a.    Virtual IP / Virtual host name for service
    b.    Some shared storage with clvmd or GFS
    c.    Way to start the application - could be some predefined template in cluster tool or your
           customer script
    d.    Way to stop the application - could be some predefined template in cluster tool or your
           customer script
    e.    How and what you want to monitor for service fail-over

in my case, VIP/Virtual_hostname is already configured in /etc/hosts. i have /u01 and /u02 as a choice for shared storage, i'll be using predefined Oracle option in luci to create HA instance of oracle with listener. Monitoring and start/stop will be handled by the same.

In Linux a service that is going to be configured is on top of a cluster and fail-over domain. service is called a "service group" and above mentioned things are called service group "resources". From one tool to the other, you may find different names. For example in service guard, a service group is called a package and all the resources are pre-reqs to build a package. in VERITAS SF, name differs slightly - but concept remains the same. i.e.

you should have one cluster - then one fail-over domain (not present in HP or VERITAS etc.) then a service group running on top of that fail-over domain with certain resources (IP, shared storage, start/stop scripts and monitoring).
With sufficient knowledge you can translate above in HP's, SUN's (now oracle) or VERITAS version.

Lets configure oracle as HA service in Redhat cluster services; configured above.

i-    Verify you have your /etc/hosts has VIP entry (already done when configuring NIC interfaces.)
ii-   Three slices have been presented to both the servers. Two disks are shared for DB data and
       quorum disk and one for oracle binary installation. you may put oracle binaries on some shared
       storage to avoid installation on secondary nodes but you 'll have configure oracle user and home
       directories accordingly.

Create storage as:

1.     # pvcreate /dev/mapper/dm-1

2.     # vgcreate -cy vgdata/dev/mapper/dm-1

3.     # lvcreate -L 10G -n lvdata vgdata

4.     # mkfs.ext4 /dev/vgdata/lvdata

5.     # vgchange -an vgdata 

6.     # pvcreate /dev/mapper/dm-2 

7.     # vgcreate  vgapp/dev/mapper/dm-2 #Note for local -cy is missing

8.     # lvcreate -L 10G -n lvapp vgapp 

9.     # mkfs.ext4 /dev/vgapp/lvapp

10.  # vgchange -an vgapp 

11.   # pvcreate /dev/mapper/dm-3

12.  # vgcreate -cy vgqrm/dev/mapper/dm-3 

13.  # lvcreate -L 2G -n lvqrm vgqrm

14.   # mkfs.ext4 /dev/vgqrm/lvqrm

      15.  # vgchange -an vgqrm

         Create mount points on root as #mkdir /u02

iii-    Access luci GUI add a failover domain - in my case its OracleHA. Failover domain is may not
         be prioritized or restricted.  
iv-    Access the resources tab in luci and starting adding resources:  
         a).   Add IP resources (service IP; the same IP that was given in /etc/hosts as VIP); in my case it
         is 192.168.0.3
         b). Add LVM HA resource. Provide resource name, and quorum disk VG name vgqrm and LV 
              name as lvqrm.
         c). Add filesystem resource. Provide resource name (database in my case), mount point (/02), 
              filesystem (ext4 in my case), LV path (/dev/vgdata/lvdata in my case) 
Note: While adding resources, keep "child resource" option in perspective. It defines order and precedence of resources added.

At this point your can submit the configuration and try starting service on either nodes. You should have VIP and /u02 available. you can check service fail-over as well.



v-    Install oracle on both nodes (on /u01 which is a local non-shared mount point). At this point,
        probably, you need to handover servers to some oracle guy to go through the OS configuration
        related to Oracle and Oracle installation.
vi-   Add Oracle resource. provide resource name and other oracle details like ORACLE_HOME and
       ORACLE_SID etc.
vii-  Add Oracle listener resource.
viii- At this point you should be able to run oracle instance on both nodes using luci GUI. If service is
       failed, refer to the cluster log files and Linux messages to know whats actually going on. Use
       clustat to verify the status of cluster and the service.